DESCRIPTION: (Applicant's Abstract) The UCLA Drug Abuse Research Center, in collaboration with the Matrix Institute on Addictions, is resubmitting a proposal for a 42-month project to examine the effectiveness of levo-alpha-aceyl methadol (LAAM) as a treatment intervention for high-risk heroin addicts with AIDS prevention aspects equal or superior to methadone maintenance (MM). The proposed study uses a repeated measures design which involves randomly assigning 300 addicts (initially selected subjects and subjects to replace attrition) to two groups, MM or LAAM maintenance, for a period of twelve months of subsidized treatment. All subjects will be assessed at the beginning of treatment, at six months, twelve months, and eighteen months after treatment entry. The specific aims of the study are: (1) to test the overall effectiveness of LAAM in reducing high-risk behaviors associated with HIV infection; (2) to determine which medication and patient characteristics contribute to improved long-term retention and clinic attendance in LAAM treatment compared with MM treatment; and (3) to compare the effectiveness of LAAM and MM in reducing HIV risk behaviors associated with heroin addiction, particularly as related to subject demographic and psychosocial characteristics. The proposed project will use repeated measures ANOVA, survival analyses, and multiple or logistic regression analyses to assess these aims.